GeeCoolGuest
GeeCoolFor HX platforms, testing is the only reliable way: run 10 minutes of all-core load in performance mode and see whether CPU Package Power holds near 55W, then compare balanced. The 265HX has a well-tuned voltage/frequency curve, so performance mode pays off — provided the chassis cooling keeps up.
Plugged in and working? Performance mode. Unplugged office? Balanced. Judge by power numbers; vendor mode names don't change the data.